In recent years, there are electronic devices, for example, a semiconductor device and the like in which a heat spreader with TIM1 and TIM2 being a highly heat conductive adhesive material added to its upper and lower surfaces is provided between a semiconductor element and a heat sink as a heat radiation technique. Further, there is also devised a heat radiation technique in which a carbon nanotube (CNT) is formed between a semiconductor element and a heat sink (see, for example, Patent Documents 1 to 3).
[Patent Document 1] Japanese Laid-open Patent Publication No. 2010-192656
[Patent Document 2] Japanese Laid-open Patent Publication No. 2010-192661
[Patent Document 3] Japanese Laid-open Patent Publication No. 2010-267706
However, the above-described heat radiation techniques using the CNT each have a problem that heat resistance increases at a joint place between the semiconductor element and the heat sink, to thereby make it impossible to perform sufficient heat radiation.